One of the great things about bitcoin is the huge quantity of information available to help you learn about it before investing. To be a successful investor in anything, you need to have conviction and to do that you need to have a great deal of information and education about what you are investing in. Without such knowledge and conviction you will do dumb things like panic sell at the first sign of trouble or correction.
There are literally dozens of books and documentaries that have been made about bitcoin, almost too many to list, which is extremely helpful for someone who is considering investing in bitcoin for the first time. I believe this is one of the main reasons why so many who started investing in bitcoin eventually turn into long-term hodlers that are passionate and outspoken about bitcoin.
In one of my favorite documentaries called God Bless Bitcoin, clergy members and rabbis are interviewed making a religious and moral case for bitcoin. Talk about having true conviction! Bitcoin is widely considered a store of value and commodity and competitor to gold, and even competitor to the dollar. I don't know anyone who thinks of ethereum or any of the other gazillion altcoins as a commodity or store of value.
You can't have such passion and conviction among so many without education, and there is no shortage of educational resources when it comes to bitcoin.
I don't know any books or documentaries that has been made about ethereum or any other altcoins. The only thing you can expect with the altcoin casino is slick marketing and hype designed to sucker you in, which is what ponzi schemes and other questionable "investments" are known to do.
My favorite Bitcoin book:
Other Bitcoin books:www.amazon.com/bitcoin-Books/s?k=bitcoin&rh=n%3A283155Some documentaries (I haven't seen all of them yet):
The Rise and Rise of Bitcoin
God Bless Bitcoin
The Legendary Treasure of Satoshi Nakamoto
Bitcoin: The End of Money as We Know It
Bitcoin Through the Lens of Buddhism
Cryptopia: Bitcoin and the Future of the Internet
Introduction to Bitcoin
The Great Reset and the Rise of Bitcoin
Magic Money: The Bitcoin Revolution
Bitcoin Beyond the Bubble
Where Did Bitcoin Come From?
The Bitcoin Exeperiment: A Crazy Idea Let Loose
The Emergence of Bitcoin: The Birth of a Revolutionary Idea